1. Field of the Invention
The invention is related to stabilizer mixtures of vinyl chloride masses.
2. Prior Art
It is known that the processing methods for polymers require relatively high temperatures. In the case of these temperatures which can reach up to 200.degree. C., the vinyl chloride polymerizates are noticeably decomposed which expresses itself strongly in the change of their color as well as in the change of their mechanical characteristics. In order to prevent such disadvantageous decomposition, the polymerizates have been mixed with stabilizers, such as, nitrogen-free keto compounds which are used alone or together with metal salts of organic carboxylic acids (German Pat. No. 1,569,407). Of such keto compounds dehydracetic acid (DHS) has proven itself above all others in practice. But DHS was not satisfactory with regard to its solubility for fluid stabilizer systems and with regard to its strong inclination for plating out. However, the keto compounds, customarily used in practice, such as, stearoyl benzoyl methane or 1-phenyl-5-methylhexandione, have also been used (German Patent Application No. 2,600,516 and German Patent Application No. 2,728,862). But these compounds also are not completely sufficient with respect to heat constancy, and in the case of the stearoyl benzoyl methanes, additionally with regard to the area of application limited to Ca/Zn-stabilizers.